mov-to-mp4-remuxer

Tiny ESM library to remux .mov → .mp4 in the browser without re‑encoding

🚀 Features

• Zero re-encoding: Pure container-level remux.
• Tiny footprint: ~5 KB gzipped.
• ESModule: Plug into any modern frontend build.
• No WASM: Just JavaScript + Typed Arrays.

📦 Installation

npm install mov-to-mp4-remuxer
# or
yarn add mov-to-mp4-remuxer

🔧 Usage

import { remuxMovToMp4 } from "mov-to-mp4-remuxer";

const movArrayBuffer = await fetch("video.mov").then((r) => r.arrayBuffer());
const mp4Bytes = await remuxMovToMp4(movArrayBuffer);

// Create a Blob for playback
const mp4Blob = new Blob([mp4Bytes], { type: "video/mp4" });
const url = URL.createObjectURL(mp4Blob);
const video = document.createElement("video");
video.src = url;
video.controls = true;
document.body.appendChild(video);

🛠 API

async remuxMovToMp4(buffer: ArrayBuffer): Promise<Uint8Array>

• buffer: Input .mov file as ArrayBuffer.
• returns: Uint8Array containing remuxed .mp4 bytes.
• throws: ParseError, UnsupportedCodecError, InvalidInputError.

📚 Supported Codecs & Containers

• Container: .mov (ISO BMFF compatible)
• Video: H.264
• Audio: AAC

Unsupported: ProRes, HEVC, fragmented tracks, edit-lists.

🧪 Testing

npm test

📦 Bundling

Built with Tsup targeting ESM:

npm run build

🤝 Contributing

1. Fork the repo
2. Create a branch
3. Submit a PR

📜 License

MIT